Several processes for the production of polycarbonate resins by transesterification reactions have been proposed. In these reactions, the catalyst employed is frequently a titanate ester, which is quite effective in catalyzing the reaction; however, residues from the titanate esters in the polycarbonate resin result in an obvious color in the resin.
Since commercially desirable polycarbonate resins are expected to be colorless, polycarbonate resins produced by the transesterification reaction employing titanate catalysts are at a disadvantage because of the color, regardless of the effectiveness or economy of the transesterification process. Accordingly, a method for effectively decolorizing such titanate catalyzed polycarbonate resins has been sought.